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Search for Fractionally Charged Particles in Proton-Proton Collisions at (Formula presented)
No full textA search is presented for fractionally charged particles with charges below (Formula presented), using their small energy loss in the tracking detector as a key variable to observe a signal. The analyzed dataset corresponds to an integrated luminosity of (Formula presented) of proton-proton collisions collected at (Formula presented) in 2016-2018 at the CERN LHC. This is the first search at the LHC for new particles with a charge between (Formula presented) and (Formula presented), including an extension of previous results at a charge of (Formula presented). Masses up to 640 GeV and charges as low as (Formula presented) are excluded at 95% confidence level. These are the most stringent limits to date for the considered Drell-Yan-like production mode
Sustainable strength enhancement of cement-clay composites through partial replacement with sewage sludge and sewage sludge ash
No full textThe increasing generation of solid waste due to rapid urbanization and population growth poses significant environmental challenges, particularly in developing countries. Among these, sewage sludge (SS) and its thermally treated form, sewage sludge ash (SSA), are critical concerns. Concurrently, the stabilization of problematic soils, such as expansive clays, is vital in geotechnical engineering. This study explores the use of SS and SSA as partial replacements for Portland cement in cement-clay composites. Samples were prepared with varying cement contents (5 %, 7 %, 10 %) and SS/SSA replacement levels (3 %, 5 %, 7 %, and 10 %), compacted at dry densities of 1.5 and 1.7 g/cm³, and cured for 7, 28, and 60 days. Unconfined compressive strength (UCS) tests demonstrated that optimal replacement levels (3–5 %) of SS and SSA improved strength, with fresh SS and SSA incinerated at 600 °C showing the highest pozzolanic activity. Microstructural analyses using X-ray diffraction (XRD) confirmed the formation of cementitious phases such as C–S–H and C–A–H, while scanning electron microscopy (SEM) revealed denser and more compact matrix structures with increased cement and SS/SSA content. These findings highlight the potential of SS and SSA in enhancing the mechanical properties of clay soils while promoting sustainable waste management and reducing reliance on conventional cement
Anxieties of a Self-Claimed Middle Power: Ruptures and Continuities in Turkish Foreign Policy in the New Millennium and the Puzzle of Ontological (in) Security
No full textThis article examines the transformation of Turkey’s foreign policy under the Justice and Development Party (AKP) through the lens of ontological security. While Turkey has historically been engaged with the European ideal as the manifestation of the ontological security, the AKP era has witnessed significant shifts driven by a multi-layered activism stemming from the self-claimed middle powerhood. The study argues that ontological security provides a crucial framework for understanding these changes, particularly Turkey’s pursuit of a stable state identity amid shifting foreign policy priorities. This study explores the ruptures and continuities in Turkey’s foreign policy and assesses how identity-based concerns shape its strategic actions. In doing so, it contributes to the broader discourse on ontological security and middle power dynamics, offering a nuanced perspective on Turkey’s evolving foreign policy and self-positioning in the international arena
What do sports coaches actually know? Development and validation of physical and technical common content knowledge test packs
No full textWhile it is widely accepted that coach knowledge plays a foundational role in coaching effectiveness, there are few validated tools to determine pre- and- in-service coaches' content knowledge (CK) levels. Thus, the aim of the present study was to develop and validate two CK test packs for developing physical and technical competence in athletes. Using convenience sampling, 2457 pre-service coaches participated in this study voluntarily. Several steps were followed for development of nine CK tests including facilitating panels, and processes for establishing content and face validities. Winstep was used to conduct Rasch analyses. Content validity was established, and the infit and outfit statistics confirmed that, with minor exceptions, all of the tests met the standards as the difficulties of questions matched respondents' knowledge levels. The item and person separation indices showed excellent and acceptable confidence levels in item difficulties and respondents, respectively. The Wright map further demonstrated that all tests had a good range of difficulty levels to discriminate different knowledge levels. Data generated through the use of these CK test packs can be used to understand the actual knowledge levels of coaches, to monitor their improvements and to inform the development of educational programs
Impact of active to inert shielding gas transition on the corrosion behavior of wire arc additively manufactured duplex stainless steel
No full textThis study systematically examined the effects of inert (pure argon) and active (argon + 2 wt% oxygen) shielding gases on the corrosion behavior of wire arc additively manufactured (WAAM) duplex stainless steel (DSS), named ArP and ArO. Active shielding gases are commonly used in arc welding to enhance arc stability and efficiency, which prompted their selection in this study. Adding 2 % oxygen introduced ∼ 0.1 % oxygen into ArO, with thermodynamic simulations suggesting potential spinel phase formation but microstructural analyses revealed more complex oxide inclusions in ArO, reducing surface homogeneity and increasing intragranular and secondary austenite formation. Kernel Average Misorientation (KAM) analysis indicated higher residual strain in these areas. Electrochemical tests, including Open Circuit Potential (OCP), Electrochemical Impedance Spectroscopy (EIS), and Potentiodynamic Polarization, demonstrated superior corrosion resistance in ArP, with higher OCP (+73 mV), corrosion potential (+39 mV), and significantly lower corrosion current density (13 μA/cm2 vs. 49 μA/cm2), leading to ∼ 3 times greater corrosion resistance. This improvement is attributed to ArP’s thicker, less defective passive layer (87.3 nm vs. 14.0 nm). Corroded surface morphology indicated selective dissolution of δ-ferrite phase and likely pitting around inclusions. These findings highlight that active shielding gas in WAAM deteriorates the corrosion resistance of DSS
Rapid and Colorimetric Detection of Carbapenem/Colistin-Resistant Bacteria by a Naked Eye and Digital Image Processing Software
No full textOwing to the global increase in carbapenem and colistin resistance, several methods have been actively used for the detection of these antibiotic-resistant bacteria. However, this emerging field still requires development of more efficient and practical diagnostic susceptibility tests for rapid, simple, and economic detection of pathogens. Herein, we prepared phenotypic and colorimetric antibiotic susceptibility tests in liquid and agar forms consisting of a natural and biocompatible pH indicator called “anthocyanins” for colorimetric detection of carbapenem/colistin resistance. The most innovative and original part of this phenotypic test, for the first time, uses plant indicators to detect carbapenem/colistin resistance within 2 h (hrs). Both commercial and clinically isolated bacterial pathogens were colorimetrically detected by a human eye in 2 h. These pathogens release acidic volatile compounds (AVCs) during their growth, resulting in an acidic reaction environment, in which anthocyanin molecules were protonated and then change the color of the susceptibility tests. The color of the susceptibility tests was analyzed by smartphone platform and mobile application to provide quick, clear, and semiquantitative results. We believe that these susceptibility tests will reduce the workload of laboratories with their ease of application and evaluation, contribute to the economy of countries by eliminating economic restrictions, and will be widely used in clinics
A rotary extrusion system with a rectangular-orifice nozzle: toward adaptive resolution in material extrusion additive manufacturing
No full textMaterial extrusion additive manufacturing (MEAM) has revolutionized the production of complex designs while minimizing the amount of effort required due to its simple production pipeline. However, MEAM naturally comes with a well-known trade-off; higher build resolution often tends to enhance the product quality at the cost of a slower build rate. Nozzles, the standard tool for thermoplastic extrusion in MEAM, have evolved into a crucial component of the process for controlling the product’s build resolution. The purpose of this study is to investigate the details of a novel extrusion system that makes use of a rotating nozzle with an unconventional aperture, in contrast to its typical (i.e., circular-orifice) counterparts. The unique nozzle configuration that lacks axial symmetry allows for precise control over the effective dimension of the extrusion via rotational guiding. By positioning the oblong orifice at intermediate orientations, the presented approach seeks to provide continuously variable intralayer and interlayer resolutions for MEAM processes. This paper explores the distinctive characteristics of this new nozzle design as well as the potential uses of the novel extrusion system. The outcomes of the conducted tests demonstrate the proof-of-concept for creating variable bead width within the layers, in addition to adaptable layer heights throughout the 3D objects. Possible limitations of the new approach and future perspectives are discussed in detail
İlişkisel Materyalizmin Mimarisi: Onto-Epistemolojik Öncüllerin Kategorik Kuruluşu
No full textThis study formulates the basic premises of materialism, which has largely lost its visibil- ity despite being one of the fundamental philosophical approaches that have been effec- tive in the development of modern scientific practice and the construction of philosophy of science, in an alternative way, and aims to develop a new materialist interpretation of it that is non-reductive, pluralistic and open to the use of more than one scientific discipline. This interpretation, expressed with the term relational materialism, first addresses matter with the concept of signifier and foregrounds the concept of beable as the general philo- sophical category of matter. Secondly, it formulates the category of beable within the irre- ducible integrity of the categories of relationality, nonstaticity, and finitude; and positions knownability in terms of its correspondence to these general onto-epistemological catego- ries. Thirdly, it clarifies the conditions of existence and knownability of particular entities under general categories based on specially corresponding onto-epistemological categories (interactability, structurability, contextuality, transformability, scale-dependency, actuality, contingency). In this respect, this study offers a pluralistic philosophical framework within which different methodological positions and scientific disciplines can be formulated and criticized based on combinations of different particular categories under general catego- ries. In the conclusion of this article, the meaning and potential of relational materialism for the development of scientific research programs are evaluated.</div
Physical and physiological characteristics of female flag football players according to playing level and positions
No full textUnderstanding and addressing the physiological aspects of a sport is crucial for tailoring effective training regimens for athletes. The increasing popularity of female flag football, particularly its inclusion in the 2028 Olympics, marks the importance of understanding the physiological characteristics associated with the sport. In this context, this study aimed to identify the physical and physiological characteristics of female flag football players according to their playing status and game positions. A total of 26 female athletes (22.7 ± 2.4 years, training age = 23.3 ± 21.9 months, weekly sport-specific training = 6 ± 1.9 hours, weekly fitness training = 3.1 ± 2.4 hours) who actively participated in flag football training and University League matches were included in the study. Athletes were categorized into “First Team” and “Reserve Team,” where both categories include all positions: defensive back (n = 10), quarterback (n = 4), rusher (n = 3), and wide receiver (n = 9). Each athlete was assessed by anthropometry (height, body mass, and body fat percentage), flexibility (sit and reach), strength (grip strength), lower body power (countermovement jump), speed (20m sprint), and change of direction (T-COD). Results of the study showed that first and reserve team players have similar anthropometric characteristics. However, first-team players exhibited significantly (p< 0.01) higher scores in countermovement jump (first-team = 30.2 ± 4.1, reserve-team = 26.2 ± 2.1) and T-COD (first-team = 10.94 ± 0.56, reserve-team = 11.61 ± 0.59) tests. On the other hand, there were no significant differences among playing positions. The findings of this study might provide a better understanding of the functional capacities of female flag football players and the selection of the athletes.</p
Numerical investigation of the coherent structures in a curved channel with a spur dike at different angles with respect to the flow directions
No full textSecondary currents formed by river meanders induce scour along the river's outer bank if the bed material is erodible. Spur dikes are constructed along the outer reach of these rivers to control the flow and prevent erosion of the outer bank. Within the bending portion of a strongly curved channel, many streamwise-oriented vortices develop. The existence of a spur dike, on the other hand, causes the formation of additional coherent structures, such as horseshoe vortices and wake vortices. The interactions between these vortices and the secondary circulation produce a highly three-dimensional complicated flow environment within the channel bend and around the spur dike. In order to analyze coherent structures and their interactions with one another, eddy resolving turbulence model, Detached Eddy Simulation was used in this study. Several spur dike configurations, namely 45°, 90°, and 135° with respect to the flow direction, were investigated to better understand the changes in the flow field and coherent structures in a 180° channel bend with flat bed. The orientation and strength of the coherent vortex forming at the center of the channel changes with the inclusion of the spur dike. There are considerable changes in the bed shear stress distribution for different spur dike orientations. Among all, the 90° spur dike appears to be the most suitable one as the area prone to large bed shear stress value is 14.2 times smaller, whereas the maximum bed shear stress is 18% smaller compared to the case without the spur dike